<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<script>
window.onload=function()
{
	var aLi=document.getElementsByTagName('li');
	
	for(var i=0;i<aLi.length;i++)
	{
		if(i%2==0)
			{
				aLi[i].style.background='#ccc';
			}
			else
			{
				aLi[i].style.background='red';
			}
	}
};
//i=i+1
//i++
//i+=1
</script>
</head>

<body>
<ul>
	<li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
</ul>
</body>
</html>
